An X-ray goods inspection apparatus is an instrument that uses the X-ray imaging principle to have such objects as industrial products, baggage and human body X-rayed to acquire information about the fine structure of the object under inspection, thereby achieving such purposes as defect determining, dangerous goods checking, medical diagnosis and so on. X-ray goods inspection apparatus is widely applied in such fields as industrial nondestructive examination, security check, medical diagnosis and treatment. At the early stage, said apparatus was a planer X-ray imaging device of film, but now is the advanced digital 3D imaging device of high definition and multi-angle of view, e.g., computed tomography (CT), capable of acquiring 3D graphics or section images of high definition, being an advanced high-end application.
In a CT device (such as industrial defect detection CT, baggage inspection CT, medical diagnosis CT and so on), it is usual to put the X-ray source at one side of the object under inspection and a detector for receiving ray at the other side. When X-ray passes through an object, its strength varies with such information as the thickness and density of the object. The strength of X-ay received by the detector includes the structural information of one angle of view of the object under inspection. If the X-ray source and detector rotate around the object under inspection, we can acquire the structural information of different angle of view. Restructuring said information by a computer system and software algorithm can obtain a 3D image of the object under inspection. At present, the CT device is securing the X-ray source and detector to a circular slip ring surrounding the object under inspection. Every round of movement in work can get an image of a section of one thickness of the object under inspection, which is called a section. The object under inspection then moves along the direction of thickness to obtain a series of sections, which put together is just a fine 3D structure of the object under inspection. Therefore, for an existing CT device, in order to acquire information of different angle of view, it has to change the position of the X-ray source, so the X-ray source and detector need to move on the slip ring. To step up the inspection, the moving speed of the X-ray source and detector is often very fast. Due to the high speed movement on the slip ring, the overall reliability and stability of the device are reduced. Besides, as hindered by the moving speed, the CT inspection speed is also limited. Although the newest generation of CT in recent years mounts the detector in a circumferential manner such that the detector does not have to move, the X-ray source still has to move on the slip ring. Besides, multiple rows of detectors may be mounted so that a plurality of section images can be obtained every round the X-ray source moves, thereby increasing the CT inspection speed, but this does not solve the problem of complex structure and low inspection speed resulted from the movement on the slip ring fundamentally.
Besides, Nuctech Company Limited manufactures a type of light source apparatus that generates distributed X-ray, exhibiting a distributed X-ray source that generates an electron beams stream by hot cathodes, scans at low energy, limits current to produce a distribution of array then performs high voltage acceleration and hits targets to generate X-ray. It further manufactures a cathode control multi-cathode distributed X-ray apparatus, exhibiting a distributed X-ray source where a plurality of cathode arrays are controlled in a certain order to generate an electron beam stream which, after being focused and limited, accelerates at high voltage and hits targets to generate X-ray. It may be a straight line or an arc structure. Using said distributed X-ray sources, and through flexible structural arrangement, this invention acquires many types of goods inspection apparatus capable of satisfying different application requirements.